Mouse peritoneal macrophages treated with LPS for 6 hours. Mouse peritoneal macrophages treated with LPS for 6 hours

MicroRNA Let-7 has abundant expression in macrophages and can repress the expression of IL-6 via binding the 3'UTR of IL-6 mRNA. Here, the IL-6 ceRNAs, which compete let-7 with IL-6, was investigated by cDNA Microarray. We reveal that RasGRP1 specifically derepress the expression of IL-6 by competing Let-7a in inflammatory response. Our data elucidated a previously uncharacterized coding-independent role of RasGRP1 in innate immunity, providing an insight into the ceRNAs modulation of innate immune response, and found that RasGRP1 have a dual-function in promoting inflammation and inhibiting tumor by a protein-independent or dependent manner respectively, which may well explain why acute inflammation rarely leads to tumorigenesis. Overall design: Comparison the expression level of Let7 target-genes in LPS or PBS treated macrophages.